This invention relates to a disposable syringe of the prefilled type. More particularly, it relates to a prefilled, disposable syringe wherein the medicament contained in the syringe is held under maximum sterile conditions until it is desired to premix it with a fluid material, the syringe then affording positive piercing sequencing by a sliding piercing member first with the medicament and subsequently the diluent and at the same moment, utilizing a minimum number of parts.
There are currently available many types of disposable syringes wherein a medicament is sealed in a syringe barrel to be later combined with a diluent for the material in the syringe barrel. There are also available unitary containers which contain a medicament and a diluent for it in two different compartments which are then intermixed prior to their usage. However, many of the devices which are now available either do not afford positive intermixing between the two materials, are costly to manufacture because of the necessity of utilizing many component parts, are complicated in their usage because of many parts being involved or after intermixing in a container still require a syringe for injection. For example, in U.S. Pat. Nos. 2,684,068; 3,098,483 and 3,327,710, combination hypodermic syringes and mixing containers are disclosed. However, these units do not afford complete separation of one of the materials to be mixed from the piercing cannula or tube so that sterility and complete mixing can be a problem. Further, many of these units as well as one of the units described in U.S. Pat. No. 3,542,023 do not afford positive engagement and sequencing of the various compartments for the components to assure their intermixing. Positive intermixing is also a factor in U.S. Pat. No. 3,724,460 which while employing a multitude of components still does not afford a positive sequencing action in the unit. In U.S. Pat. Nos. 3,489,147 and 3,477,432, multicomponent combination mixing and administration syringes are disclosed. However, various manipulations of these units must be made as well as an undesirable cost factor in manufacturing a double-barreled type syringe.
It is an advantage of the present invention to afford a novel combined mixing and hypodermic syringe which affords maximum isolation and sterility of two components which are to be ultimately mixed and positive sequencing of the intermixing. Other advantages are a syringe which requires a minimum number of parts, minimum manipulations, preassembly of certain components without accidental engagement and a syringe system which utilizes a minimum amount of space for packaging.